Chris's Wiki :: blog/linux/FedoraWeakUpdatesFailure

Recently I blamed DKMS for building one of my kernel modules for the wrong kernel. It turns out that this is not quite what happened, and in fact what happened is Fedora's fault. I found this out when I did yet another unsuccessful kernel upgrade attempt on my work machine, had the module problem happen again, and paid close attention to what was actually in my module directory (partly because this time around I was sure I'd checked for the problem before I'd rebooted).

As part of their customized kmod package, Fedora ships a program, /usr/sbin/weak-modules, which apparently comes from Red Hat Enterprise and which exists to, well, let me quote the comment at the start of the shell script:

weak-modules - determine which modules are kABI compatible with installed kernels and set up the symlinks in /lib/*/weak-updates.

This is the best documentation we have for the program because Fedora has not provided a manual page. Well, actually the current DKMS manual page says something about this, and what it says is so incredible that I'm going to quote it almost in full, with emphasis mine. This is from the section where it talks about various parameters you can set in a module's dkms.conf:

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